Contribution to the study of varroa disease

Part 1 of this thesis is a literature survey with 32 references. In Part 2 the examination of 5 samples of worker brood and 7 of drone brood, from Varroa-infested colonies, is described. Information on the development of Varroa larvae in cells with worker larvae confirmed previously published reports. Results for larvae in drone cells were difficult to interpret. Part 3 consists of results of laboratory tests of the treatment of infested bees with Folbex-VA.